Switch Slack to Flathub instead of the packagecloud apt repo

Adds a shared ensure_flatpak helper in lib.sh (installs flatpak + adds the
Flathub remote) and reuses it from both the slack module and desnap.sh's
unmapped-snap fallback instead of duplicating the setup.

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2023 Ian Andwati
+Copyright (c) 2026 Ian Andwati
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

desnap.sh

@@ -127,11 +127,7 @@ fi
 
 if [[ ${#unmapped[@]} -gt 0 ]]; then
   warn "no apt equivalent known for: ${unmapped[*]} — setting up Flatpak/Flathub so you can still get them"
-  apt_install flatpak
-  if has_cmd gnome-shell; then
-    apt_install gnome-software-plugin-flatpak
-  fi
-  sudo flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo
+  ensure_flatpak
   warn "search/install with: flatpak search <name>   &&   flatpak install flathub <app-id>"
   for s in "${unmapped[@]}"; do
     warn "  - $s"

install/install.sh

@@ -41,7 +41,7 @@ declare -A MODULE_DESC=(
   [zig]="Zig + zls (language server)"
   [chrome]="Google Chrome"
   [discord]="Discord"
-  [slack]="Slack"
+  [slack]="Slack (Flathub)"
   [firefox]="Firefox (Mozilla apt repo, not snap)"
   [postman]="Postman"
   [jetbrains-toolbox]="JetBrains Toolbox"

install/lib.sh

@@ -48,6 +48,17 @@ apt_install() {
   fi
 }
 
+# ensure_flatpak — installs flatpak (+ GNOME Software integration when
+# running GNOME) and adds the Flathub remote system-wide. Shared by any
+# module that prefers a verified Flathub app id over a vendor's own apt repo.
+ensure_flatpak() {
+  apt_install flatpak
+  if has_cmd gnome-shell; then
+    apt_install gnome-software-plugin-flatpak
+  fi
+  sudo flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo
+}
+
 # apt_add_repo <list-name> <keyring-path> <key-url> <repo-line>
 # Registers a signed apt repo the way every vendor's official install docs do
 # it (dearmor the key into /etc/apt/keyrings or similar, write a .list file),

install/modules/slack.sh

@@ -1,7 +1,10 @@
 install_slack() {
-  if has_cmd slack; then ok "slack already installed"; return; fi
-  apt_add_repo slack /etc/apt/trusted.gpg.d/slack.gpg \
-    https://packagecloud.io/slacktechnologies/slack/gpgkey \
-    "deb https://packagecloud.io/slacktechnologies/slack/debian/ jessie main"
-  apt_install slack-desktop
+  if flatpak list --app 2>/dev/null | grep -q com.slack.Slack; then
+    ok "slack already installed"
+    return
+  fi
+
+  ensure_flatpak
+  sudo flatpak install -y flathub com.slack.Slack
+  rollback_push "sudo flatpak uninstall -y com.slack.Slack"
 }